using System.Collections.Generic;
using UnityEngine;
using System.Drawing;
using System.Drawing.Imaging;
using UnityEngine.UI;

public class DongTu : MonoBehaviour
{
    public string GifName;
    UnityEngine.UI.Image image;
    public float Mytime = 0.05f;
    List<Texture2D> zhen;
    Sprite sprite1;
    
 
int dex = 0;
    float time;
    public int x, y;


    private void Awake()
    {
        image = GetComponent<UnityEngine.UI.Image>();
        string path = "";
        if (Application.platform == RuntimePlatform.WindowsEditor || Application.platform == RuntimePlatform.WindowsPlayer || Application.platform == RuntimePlatform.OSXEditor)
        {
            path 
 
= string.Format("{0}/StreamingAssets/", Application.dataPath);
        }
        else if (Application.platform == RuntimePlatform.Android)
        {
            path = string.Format("{0}!/assets/", Application.dataPath);
        }
        else if (Application.platform == RuntimePlatform.IPhonePlayer)
        {
            path 
 
= string.Format("{0}/Raw/", Application.dataPath);
        }
        zhen = GifToTextureByCS(System.Drawing.Image.FromFile(path + "/"+ GifName + ".gif"));
        x = zhen[0].width;
        y = zhen[0].height;
    }

    // Use this for initialization
    void Start()
    {

    }

    void Update()
    {
       
        sprite1 = Sprite.Create(zhen[dex], new Rect( 0, 0, x,y), Vector2.zero);


        image.sprite = sprite1;

        time += Time.deltaTime;
        if (time > Mytime)
        {
            dex++;
            if (dex == zhen.Count)
            {
                dex = 0;
            }
            time = 0;
        }
    }

    /// <summary>
    /// gif轉換圖片
    /// </summary>
    /// <param name="image"></param>
    /// <returns></returns>
    List<Texture2D> GifToTextureByCS(System.Drawing.Image image)
    {
        List<Texture2D> texture2D = null;
        if (null != image)
        {
            texture2D = new List<Texture2D>();
            //Debug.LogError(image.FrameDimensionsList.Length);
            //image.FrameDimensionsList.Length = 1;
            //根據指定的唯一標識建立一個提供獲取圖形框架維度資訊的例項;
            FrameDimension frameDimension = new FrameDimension(image.FrameDimensionsList[0]);
            //獲取指定維度的幀數;
            int framCount = image.GetFrameCount(frameDimension);
            for (int i = 0; i < framCount; i++)
            {
                //選擇由維度和索引指定的幀;
                image.SelectActiveFrame(frameDimension, i);
                var framBitmap = new Bitmap(image.Width, image.Height);
                //從指定的Image 建立新的Graphics,並在指定的位置使用原始物理大小繪製指定的 Image;
                //將當前啟用幀的圖形繪製到framBitmap上;
                System.Drawing.Graphics.FromImage(framBitmap).DrawImage(image, Point.Empty);
                var frameTexture2D = new Texture2D(framBitmap.Width, framBitmap.Height);
                for (int x = 0; x < framBitmap.Width; x++)
                {
                    for (int y = 0; y < framBitmap.Height; y++)
                    {
                        //獲取當前幀圖片畫素的顏色資訊;
                        System.Drawing.Color sourceColor = framBitmap.GetPixel(x, y);
                        //設定Texture2D上對應畫素的顏色資訊;
                        frameTexture2D.SetPixel(x, framBitmap.Height - 1 - y, new Color32(sourceColor.R, sourceColor.G, sourceColor.B, sourceColor.A));
                    }
                }
                frameTexture2D.Apply();
                texture2D.Add(frameTexture2D);
            }
        }
        return texture2D;
    }

}

需要引用System.Drawing.dll